Networks

Introduction Since the early 1990s there has been a tremendous growth in the piano tuner community. The modern idea of radio networking was first introduced in the late 60s at the University of Hawaii with the ALOHANET. The ALOHANET was utilise to get in touch the different campus locations on the Hawaiian Islands. The history of wireless networking stretches far back than you might think. It was over fifty years ago, during orb War II, when the United States Army first used wireless signals for data contagion. They developed a radio data transmittance technology, which was heavily encrypted. It was used quite extensively throughout the exploit with the US and her allies. This inspired a group of researchers in 1971 at the University of Hawaii to create the first packet based radio communications network. ALOHNET, as it was named, was essentially the very first wireless local area network (WLAN). [2] Figure 1 - fair WLAN using 802.1x from Lecture13 notes. Frequency-hopping spread spectrum The implementation of a wireless LAN is done with the use of radio-frequency technology. The two technologies that are used in wireless LANs that include frequency-hopping and direct- while spread-spectrum.

Frequency-hopping spread spectrum (FHSS) is a order of transmitting radio signals by rapidly switching a carrier among many frequency channels, using a pseudorandom sequence cognize to both transmitter and receiver.[3] This technology was developed during WWII by the Army Signal Corps in a form called SIGSALY. SIGSALY was initially used for communication between Roosevelt and Churchill; this was not known for some years because the development of SIGSALY was classified top secret.[8] under this type of communication more bandwidth is used than the usual transmission in which only a single frequency is used. This increase bandwidth is due to the signal being spread over a greater number of frequencies. FHSS is the process of hopping from one... If you want to get a full essay, order it on our website: Orderessay

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